Testing for substance abuse has become standard procedure in a variety of settings such as employment, schools, sports, and law enforcement. The industry has so far provided a great variety of easy-to-use collecting and testing devices which can be utilized by technicians with limited training in the field for preliminary test purposes.
Due to the speed at which the devices of the prior art are used, the relative lack of sophistication of the technicians, and the less than propitious environment of the test, it has become desirable, if not mandatory, to preserve an aliquot of the sample fluid for further testing and validation under more controlled conditions to seek to confirm the results of the earlier preliminary test.
U.S. Patent Application Publication No. US2005/0202568 A1 Tung et al. dated Sep. 15, 2005, incorporated herein by this reference, discloses a sophisticated device which provides for the preservation of part of the fluid specimen in a sealed plastic reservoir for confirmatory testing at a later date. Such a sophisticated device can be costly to manufacture, requires more operator skill and time to use, and is more susceptible to manufacturing or use errors.
It is well known that small amounts of analytes, such as those associated with marijuana or other abused drugs, can be adsorbed over time on the surfaces of fluid specimen containers. Such adsorption reduces the concentration of analytes remaining in the specimen leading to inaccuracies in testing results associated with detection of those analytes. This problem can be exacerbated by containers used to transport specimens for confirmatory testing where the specimen remains in the container for longer periods and is subjected to agitation and temperature changes during transport. It is therefore desirable to preserve an aliquot of the fluid specimen in such a way as to minimize adsorption of target analytes on the aliquot container surfaces.
The invention results from an attempt to devise a simpler apparatus that reduces some of the above identified problems.